I absolutely loved this scenario. It had great atmosphere, lots of storyline advancing information and enough fights to keep my ADD barbarian sated. I understand where people say it's an easy TPK, but any slightly prepared pathfinder group shouldn't have too much of a problem with this scenario.
I loved the flavor of this scenario. All of the spooky scenarios and modules (Feast of Ravenmoor, From Shore to Sea, Haunting of Hinojai, etc.) are awesome in my opinion. Our GM (Dennis Wheelock. Thanks Dennis!) provided plenty of descriptions of creepy lightning strikes, strange organ music and odd tracks all around the building. Maybe it was all just our haunted Oracle, though.
The advancement in the overarching Pathfinder Society plot was amazing. As someone who played The Disappeared, The Blackros Matrimony and Fortress of the Nail, I loved all the handouts. They gave so much insight as to what was going on, and perhaps what will happen in the future!
The "surprise": Our group completely ruined the "surprise" at the end. As soon as we met the little girl our alarms went off. She was seemed to be sustaining quite well for the lack of food and there weren't any signs of long occupancy, so we were all a little edgy. Eventually, my stupid barbarian walked up to her and just went, POKE! Failed the will save, so it still seemed like I just poked a little girl in the eye. The oracle said "I have a way to tell if she's human or not," and all hell broke loose. Needless to say, she began panicking, which led to initiative and her being grappled by the monk. Boss fight over.
The "TPK": As for the Babau, we had no trouble with him due to our Aasimar cleric. As soon as the darkness went down, daylight went up. People are complaining that PC's need to bring a level 3 spell as a level 3 caster, but you don't. Any prepared PC will have spent either 300 gold on a Potion of Darkvision or 750 on an oil of daylight. We're Pathfinders, not untrained mercenaries.